1. Field of the Invention
The invention relates to a transdermal dosimeter, a device used to monitor human and animal exposure to chemical agents and drugs.
2. Brief Description of Related Art
A transdermal dosimeter, is a device used to monitor human exposure to chemical agents; it is based on the principle that many chemical agents are excreted through the skin in small quantities. The chemical agents may be: (a) exogenous--e.g., drugs of abuse, environmental pollutants, prescription drugs, herbicides, pesticides and the like; (b) endogenous--e.g., hormones, or metabolites such as glucose, creatinine, electrolytes or the like.
The advantage of a transdermal dosimeter is that it provides quantitative information about the mean integrated exposure to chemical agents over long periods (e.g. several hours or days), and provides evidence of exposure even after the agent may have been completely metabolized or excreted from the body. Representative of transdermal dosimeters are those described in U.S. Pat. Nos. 4,329,999; 4,595,011; and 4,706,676.
Frequently in the course of medical treatment, it is important for the physician to determine whether or not the patient is following a prescribed medical regimen, or is using alcohol or non-prescribed drugs. It is often the case that the patient does not disclose the relevant information accurately. Thus, there is a need for a monitoring device that could be used with convenience by the patient and which would yield accurate and precise information to the physician.
One of the problems or potential problems associated with the presently available devices described above, is the ability of the patient or other to remove the device from the skin for periods of time, without the physician's knowledge. This interruption of monitoring or pharmaceutical delivery, whether accidental or deliberate, knowingly or through lack of instruction, can result in inaccurate information or wrong assumptions being given to the physician.
The present invention constitutes an improvement over the devices described in the above prior art patents. The improved devices of the present invention function to alert a physician or other health-care personnel to incidences where the device has been removed, even temporarily, from the patient.